Update: 12.3 kW Solar System

jebatty

Minister of Fire
Jan 1, 2008
5,747
Northern MN
2020 continues on a track of record high kWh for our solar PV system in northern Minnesota. After a dismal all-time record low month of January with 473 kWh vs January average of 710 kWh, 2020 has beat the 5 year average every month February through July, with July setting an all-time record high of 1950 kWh vs July average of 1795 kWh and the prior all-time high of 1923 kWh in July 2014. With five months yet to go in 2020, the record setting production has plenty of time to reverse course ... or set a new high record year.

I'm using the 5-year period 2014-2018 as a fixed average with the thought that this time period should reflect production with least impact of any panel degradation, and that over time panel degradation should start to be evident. I believe that degradation of 1/2 of 1% per year is an industry standard. After nearly 7 years I don't see any degradation trend.

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DuaeGuttae

Minister of Fire
Oct 26, 2016
603
Texas
Thanks for sharing this, jebatty. I actually just reread your 15-page thread on your original and enlarged installation. We’re looking at our solar options here in sunny Texas, and I’ve been reading past threads. I appreciate the insights you share and the questions and comments others provide.
 

ABMax24

Feeling the Heat
That's actually pretty impressive. This is our second year of production and we still don't have a noticeable drop in output. Although my last couple months data is inaccurate as Neurio was bought by Generac and my energy charts don't line up with my power charts and I can't seem to get Generac to understand the problem let alone fix it.

Is there anything you'd do different if you did it again? Would you still go with micro-inverters or would you choose a string inverter?
 

jebatty

Minister of Fire
Jan 1, 2008
5,747
Northern MN
Is there anything you'd do different if you did it again? Would you still go with micro-inverters or would you choose a string inverter?
I would have installed initially the maximum kW array that I could backfeed to the grid under net metering. At least I had the foresight when installing the first 26 panels in 2013 to install underground wiring to allow a 20 panel expansion in 2015 which brought me to that maximum.

I also think I would have gone with string inverter(s). My micros are no longer made, but I did buy a few extra to replace a couple of possible future failures. Still, I have had just shy of 7 years of trouble free performance (except one micro failed early on, a 10 minute job to replace). String inverters and panels with optimizers seem to have greatly improved, and it doesn't seem that micros are a major player in the PV arena.